Egypt. J. Soil Sci. (2015)5:1-16
Heavy metals accumulation in the edible vegetables grown on contaminated soils Youssef, M. A.1 and Eissa, M. A.2 1Department
of Soils and Water, Faculty of Agriculture, Al-Azhar University, Assiut 71524, Egypt
2Department
of Soils and Water, Faculty of Agriculture, Assiut University, Assiut 71526, Egypt Email of the corresponding author:
[email protected]
Abstract Nowadays, using sewage wastewater for agriculture production is commune practice creating hazardous environment impacts. Assessment of these negative effects is a vital issue to prevent heavy metals to be introduced in the food chain. Three sites were chosen (Ellwan, Mangabad and El-Madabegh villages, Assiut Governorate) during 2012 and 2013 seasons in order to evaluate heavy metals concentrations in vegetable crops. Three types of vegetable crops vary in their edible part (leaves, roots and fruits) which irrigated by sewage wastewater (SW) or ground water (GW) were collected from the different sites and analyzed for their Fe, Mn, Zn, Cu, Cd, Ni and Pb contents. The obtained results showed that the edible leaves of lettuce, cabbage and spinach contained high concentration of heavy metals compared to the carrot, turnip and onion roots. The highest concentrations of heavy metals were recorded in spinach leaves irrigated by SW. The lowest concentrations of heavy metals were realized in okra fruits compared to other fruity vegetable crops (squash and tomato). All vegetable crops irrigated by GW contained low concentrations of heavy metals compared to those irrigated by SW. Soil of all villages were contaminated by heavy metals either those irrigated by SW or GW. It is worthy to mention that irrigated edible crops especially spinach, onion, turnip and carrot by SW should be avoided. The potential hazards for humans and animals health were shown due to the high uptake of heavy metals especially Zn, Cd and Pb. Key word: Heavy metals accumulation, Sewage wastewater, Edible vegetables, Ground water. Introduction Water is a vital for all living creature, it makes up to 50-97% of plant and animal and about 70% of human body weight (Buchholz, 1998), but regrettably it is the most poorly managed resource in the world (Fakayode, 2005). Ground water (GW) resources in most areas of the world are shrinking at an alarming rate and may not meet the ever increasing demands from 1
M. A. Youssef. and M. A. Eissa agriculture and industry in future. Estimates revealed that agriculture sector consumes maximum of the GW and~80 percent of actual water resources are utilized in agriculture for irrigation purpose. Many farmers in areas near to urban/per-urban localities are even compelled to use wastewater to irrigate their crops, due to absence of better alternatives (Ghimire, 1994). The volume of sewage wastewater (SW) generated by domestic, industrial and commercial sources has increased with population, urbanization, improved living conditions and economic development (Qadir et al., 2008). In many developing countries, urban and per-urban agriculture depends, at least to some extent, on wastewater as a source of irrigation water. The water quality and the conditions under which this water is used vary greatly. Quality of the wastewater used and the nature of its use vary enormously, both between and within countries. In many low-income countries in Africa, Asia, and Latin America, the wastewater tends to be used untreated, while in middle-income countries treated wastewater is used (Faruqui et al., 2004). Sewage wastewater (SW) provides farmers with a nutrient enriched water supply and society with a reliable and inexpensive system for wastewater treatment and disposal (Ullah et al., 2011 and Gosh et al., 2012). In many situations, Egyptian farmers prefer wastewater even when freshwater is available, because they earn higher profits by using it. Wastewater can be a more reliable source, both in terms of availability and volume, than either rain or freshwater supply from irrigation systems. Chhabra (1989) found that SW contained 48.3, 7.6, 72.4 and 34.6 mg L-1 of N, P, K and S, respectively besides their micro-nutrient (0.34, 10.8, 0.2 and 0.36 mg L-1 for Zn, Fe, Cu and Mn, respectively). Thus, five irrigations of 7.5 cm each with SW could add about 181, 29, 270 and 130 kg ha-1 of N, P, K and S, respectively which is adequate to meet the nutrient requirement of the crops. Computations made on the basis of an average content of N, P and K in WW and ~70% utilization in agriculture sector shows that WW can annually contribute 380, 60, 520 and 1.4 thousand tons of N, P, K and Zn, respectively, in addition to other micro-nutrients. These findings, recapitulates that waste water have great potential as manure when used to irrigate crops. Waste waters are contaminated with trace elements like lead (Pb), cobalt (Co) chromium (Cr) and arsenic (As) which they are non-essential and over time toxic to plants, animals and human beings (Kanwar & Sandha, 2000). Long-term application of treated and untreated waste water resulted in significant buildup of heavy metals in soil (Khan et al., 2008; Ullah et al., 2011 and Gosh et al., 2012) and in vegetables and cereals and their subsequent
Egypt. J. Soil Sci. (2015)5:1-16 transfer to food chain causing potential health risk to consumers (Singh et al., 2010 and Gupta et al., 2011). Heavy metal concentrations in plants grown in wastewater-irrigated soils were significantly higher than that grown in fresh water-irrigated one. (Khan et al., 2008; Singh et al., 2010 and Gupta et al., 2011). Sharma et al., (2006) concluded that the use of treated and untreated wastewater for irrigation had increased Cd, Pb, and Ni contamination in edible portion of vegetables causing potential health risk over long term. Chary et al. (2008) assessed Zn, Cr, Cu, Ni, Co and Pb in soils, forage grass, milk from cattle, leafy and non-leafy vegetables, which could be emplacing for people known to consume these contaminated product. Using sewage water to irrigate crops is an old practice in many areas of Egypt. In order to provide food for ever-increasing population and due to the unavailability and scarcity of irrigation water, sewage water is used for irrigation purpose. Which may cause soil pollution and contamination the grown crops. The present study was undertaken to assess the heavy metals on edible vegetables irrigated by sewage wastewater. Material and Methods 1- Site description and Sampling Three sites were chosen (Ellwan, Mangabad and El-Madabegh villages, Assiut governorate, Egypt) which is situated at 27 12- 16.67= N latitude and 31 09- 36.86= E longitude, during 2011/12 and 2012/13 in order to evaluate heavy metals concentration in grown vegetable crops. The soils in these villages have been irrigated by raw sewage wastewater for 50 years ago. Two locations in each village were chosen to collect random vegetable samples from the grown crops (lettuce, cabbage, spinach, carrot, turnip, onion, okra, tomato and squash). Composite sample consisting of the edible portion of ten plants of each crop was selected except for cabbage crop only a head was picked. The vegetable samples were washed by tap water twice and rinsed by distilled water, oven-dried at 70 oC to a constant weight ground in a stainless steel mill and passed through a 0.5 mm sieve and they were kept for chemical analysis. Six samples of soil, ground water and sewage wastewater were collected from each location and they were subjected for chemical analysis. 2- Water, soil and plant analysis Wastewater samples were pretreated by concentrated HNO3 to prevent heavy metals microbial degradation. Both treated wastewater and ground water samples (50 ml) were digested 3
M. A. Youssef. and M. A. Eissa with 10 ml concentrated HNO3 at 80 0C according to APHA (2005) and determined for heavy metals as shown in table (1). Table (1) Heavy metal concentrations in ground and sewage wastewater in the studied area Heavy metal concentrations (ppm) Water type Fe Mn Zn Cu Pb Cd Ni GW 0.5 0.8 0.08 0.04 0.0 0.0 0.0 SW 3.0 1.3 0.5 0.3 1.0 0.05 0.03 PL* 5 2 0.2 0.2 5 0.01 0.2 *Permissible limits according to FAO (1985)
Composite soil samples (2.0g) were digested in a mixture of HF-HNO3-HClO4-H2SO4 in Teflon beakers to extract total heavy metals content and determined according to Baker and Amacher (1982) as shown in table (2). Plant samples (0.5g) were incinerated in a muffle furnace at 500 0C. Dry ashes were solubilized in concentrated HCl and they were subjected for heavy metals analysis. Heavy metals (Fe, Mn, Zn, Cu, Pb, Cd and Ni) concentrations in wastewater, soil and edible parts of vegetable samples after digestion were determined using Inductivity Coupled Plasma Emission ICP 6200. Table (2) Mean values of heavy metal contents in the studied soil area Total heavy metals (mg⁄kg) metals Fe Mn Zn Cu GW irrigated soil 4000 180 160 98 SW irrigated soil 7000 400 640 305 PL* 5000 200 300 100
Pb 95 304 100
Cd 1.0 5.4 3
Ni 45 120 50
*Permissible limits according to European Union Standards (EU, 2002) and Bigdeli and Mohsen (2008).
Data of plant analysis were standard deviation, average, minimum and maximum values were calculated using EXEL software program. Results and Discussion I. Iron (Fe) Data illustrated in table (3) show that average iron (Fe) concentration reached to 187 mg kg-1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while its average concentration was about 107 mg kg-1 in those irrigated by ground water. Average iron (Fe) concentration was about 83 mg kg-1 in the root dry matter of carrot, turnip and onion irrigated by sewage wastewater, while its average concentration was about 61.3 mg kg-1 in those irrigated by ground water. Iron (Fe) concentrations ranged from 53 to 70 mg kg-1 in the fruit dry matter of okra, tomato and squash irrigated by sewage wastewater, compared with 38 to 55 mg kg-1 in those irrigated by ground water. It can be concluded that irrigated by sewage wastewater
Egypt. J. Soil Sci. (2015)5:1-16 increased Fe concentration in leafy vegetables, edible roots and fruit by about 43.14, 26 and 27.6% respectively compared to irrigate by ground water.
Irrig. water
Table (3) Iron concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water Value Min SW
Max Mean
#
Min GW
Max Mean# PL*
Fe Content (mg kg-1 Dry wt.) Roots Carrot Turnip Onion
Lettuce
Leaves Cabbage
Spinach
Okra
Fruits Tomato
Squash
150
150
160
60
75
70
45
50
50
230
240
200
90
120
90
70
80
80
187.50±28.0
190.83±26.1
181.67±13.4
77.08±9.6
93.00±15.8
79.42±7.5
53.33±6.9
69.17±10.0
70.42±9.6
85
90
85
40
45
40
30
40
30
170
125
110
80
95
70
50
70
75
119.17±27.3
105.00±11.9
94.75±8.5
61.58±11.4
67.67±13.8
53.75±8.6
38.33±6.9
55.00±7.7
45.83±14.4
From 350.61to 425.50
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
The Fe concentration in the edible portions which vary between different vegetable varieties could be arranged in descending order of leave > root > fruit. Although using sewage wastewater in irrigation increase Fe concentrations in the edible portions of vegetables, all the Fe concentrations are still within the permissible limits. This may be due to their structures and assimilation capacities. (Khan et al., 2008; Singh et al., 2010 and Gupta et al., 2011). II. Copper (Cu) Average copper (Cu) concentration was about 18 mg kg -1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while its concentrations was about 6.7 mg kg-1 in those irrigated by ground water (table 4). Average Cu concentration was about 16 mg kg-1 in the root dry matter of carrot, turnip and onion irrigated by sewage wastewater, while its concentration was about 7 mg kg-1 in those irrigated by ground water. The mean values of copper was 13.5 mg kg-1 in the fruit dry matter of okra, tomato and squash irrigated by sewage wastewater, while its concentrations was about 7 mg kg-1 in those irrigated by ground water. It can be concluded that irrigated by sewage wastewater increased Cu concentration in the leafy vegetables, edible roots and fruit by about 62.96, 56.25 and 50.00% respectively compared to irrigate by ground water. The variation in heavy metal concentrations in vegetables may be due to variation in their absorption, and accumulation tendency (Khan et al., 2008). The Cu concentration in the edible portions could be arranged in descending order of leave > root > fruit. Table (4) Copper concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water 5
Irrig. water
M. A. Youssef. and M. A. Eissa
Value Min
SW
Max Mean
GW
Cu Content (mg kg-1 Dry wt.)
#
Min Max Mean# PL*
Lettuce
Leaves Cabbage
Spinach
Carrot
Roots Turnip
Onion
Okra
Fruits Tomato
Squash
13
12
15
14
13
12
11
12
11
20
20
30
20
20
15
18
15
15
16.4±2.4
15.9±2.8
21.8±5.4
16.7±1.8
16.6±2.3
13.8±0.9
13.8±2.1
13.3±1.1
13.4±1.6
3.0
4.0
5.0
5.0
5.0
5.0
5.0
5.0
5.0
8.0
9.0
9.0
9.0
9.0
9.0
7.0
8.0
9.0
6.3±1.5
6.9±1.6
7.3±1.2
6.9±1.1
7.2±1.5
7.4±1.2
5.6±0.7
6.8±1.0
6.9±1.2
From 40 to 73.30
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
Although using sewage wastewater in irrigation increase Cu concentrations in the edible portions of vegetables, all Cu concentration are still within the permissible limits. Similar results were obtained by Fytianos et al. (2001) who observed that Cu contents in vegetables grown in urban and rural areas did not vary significantly while Farooq et al. (2008) found that Cu contents in the edible vegetable were below 10 mg kg–1. III. Manganese (Mn) Data in table (5) show that the mean values of Mn concentrations was 87 mg kg-1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while it 72 mg kg-1 in those irrigated by ground water. The mean values of Mn concentrations was 81 mg kg-1 in the root dry matter of carrot, turnip and onion irrigated by sewage wastewater, while it was 60 mg kg-1 in those irrigated by ground water. Manganese concentrations ranged between 68-89 mg kg-1 in the fruit dry matter of okra, tomato and squash irrigated by sewage wastewater, while it ranged between 45-69 mg kg-1 in those irrigated by ground water.
Irrig. water
Table (5) Manganese concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water Mn Content (mg kg-1 Dry wt.) Value Min SW
Max Mean
#
Min GW
Max Mean# PL*
Lettuce
Leaves Cabbage
Spinach
Carrot
Roots Turnip
Onion
Okra
Fruits Tomato
Squash
70
80
70
60
70
70
80
50
50
100
100
110
90
110
90
100
80
80
82.5±8.7
87.5±6.2
90.3±10.4
76.3±8.8
86.9±11.9
78.6±6.8
88.8±8.6
67.5±9.7
67.9±8.9
50
60
60
35
45
40
50
40
30
80
80
85
85
90
60
85
60
70
65.8±10.2
70.8±4.7
77.9±6.9
58.7±14.4
68.3±14.9
52.5±6.9
69.0±10.7
52.9±7.5
44.6±12.0
From 300 to 500
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
The Mn concentrations in the studied vegetables still within the permissible limits and it could be arranged in descending order of leave > root > fruit. It can be concluded that irrigation
Egypt. J. Soil Sci. (2015)5:1-16 with sewage wastewater increased Mn concentration in the leafy vegetables, edible roots and fruit by about 17.24, 25.62 and 25.87% respectively compared to irrigate by ground water. The elevated metal concentrations in the food crops may have been enhanced due to mining activities as can be deduced from the analysis of the pollution load index of soils from irrigated by sewage water with respect to those sampled from irrigated by ground water areas. IV. Zinc (Zn) Data in Table (6) show that the mean values of Zinc (Zn) concentrations was 91 mg kg-1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while it was 65 mg kg-1 in those irrigated by ground water. The mean values of Zn concentrations was 58 mg kg-1 in the root dry matter of carrot, turnip and onion irrigated by sewage wastewater, while it was 38 mg kg-1 in those irrigated by ground water. Zn concentrations ranged between 40-54 mg kg-1 in the fruit dry matter of okra, tomato and squash irrigated by sewage wastewater, while its concentrations ranged between 27-38 mg kg-1 in those irrigated by ground water. Sewage wastewater increased Mn concentration in the leafy vegetables, edible roots and fruit by about 29.2, 34.29 and 32.87% respectively compared with ground water. Zn concentrations in the edible parts of vegetables were above or exceeded the permissible limits.
Irrig. water
Table (6) Zinc concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water Zn Content (mg kg-1 Dry wt.)
SW
GW
Value
Lettuce
Leaves Cabbage
Spinach
Carrot
Roots Turnip
Onion
Okra
Fruits Tomato
Squash
Min
50
70
90
50
50
40
35
35
40
Max
80
90
150
70
75
55
60
55
60
Mean#
72.5±9.7
78.3±7.2
122.5±18.7
63.3±8.7
62.1±8.9
50.0±5.2
48.8±9.1
40.4±6.2
53.8±6.8
Min
40
60
40
25
20
30
20
20
30
70
80
80
55
40
60
35
40
50
61.7±1.05
67.9±6.6
63.8±13.8
37.1±8.4
30.8±5.6
47.1±7.8
26.7±4.4
30.8±7.3
37.5±6.6
Max Mean# PL*
From 60 to 80
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
The Zn concentration in the edible portions could be arranged in descending order of leave > root > fruit. Zn concentrations vary, it according to different capacities for absorbing metals. Ahsan et al. (2011) investigated heavy metal contents in edible portion of vegetables and found that Zn, Cu, Pb, Ni, Cd and Cr contents were higher than the safe limits. Similar results were reported by Khan et al., 2008; Singh et al., 2010 and Gupta et al., 2011. V. Nickel (Ni)
7
M. A. Youssef. and M. A. Eissa Data illustrated in table (7) show that the mean value of Nickel (Ni) concentrations reached to 3.47 mg kg-1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while it was about 0.85 mg kg-1 in those irrigated by ground water.
Irrig. water
Table (7) Nickel concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water Ni Content (mg kg-1 Dry wt.) Value Min SW
Max Mean
#
Min GW
Max Mean# PL*
Lettuce
Leaves Cabbage
Spinach
Carrot
Roots Turnip
Onion
Okra
Fruits Tomato
Squash
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
6.0
6.0
7.0
6.0
6.0
7.0
5.0
5.0
3.0
3.3±1.5
3.0±1.5
4.1±1.7
3.5±1.8
3.2±1.4
4.2±1.6
2.4±1.1
2.6±1.2
1.6±0.7
0.1
0.2
0.5
0.1
0.5
0.1
0.1
0.4
0.2
1.0
1.0
2.0
1.0
3.0
0.7
0.4
1.0
0.5
0.5±0.2
0.6±0.2
1.4±0.6
0.4±0.2
1.8±0.7
0.5±0.2
0.2±0.1
0.5±0.2
0.4±0.1
From 10 to 67.90
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
The mean value of Ni concentrations was 3.61 mg kg-1 in the root dry matter of carrot,
turnip and onion irrigated by sewage wastewater, while it was 0.92 mg kg-1 in those irrigated by ground water. Average Ni concentrations ranged between 1.58-2.58 mg kg-1 in the fruit dry matter of okra, tomato and squash irrigated by sewage wastewater, while it ranged between 0.24-0.48 mg kg-1 in those irrigated by ground water. Nickel concentration in the edible portions could be arranged in descending order of leave > root > fruit. It can be concluded that irrigation with sewage wastewater increased Ni concentration in the leafy vegetables, edible roots and fruit by about 75.5, 74.63 and 83.59% respectively compared to irrigate by ground water. These results was in accordance to those examined by Demirezen & Aksoy (2006) who found that nickel concentration to be high in vegetables grown in urban area (1.8-13.45 mg kg–1) than the same vegetables grown in rural area (0.44-4.02 mg kg–1 ) of Turkey but nickel was found to be within the safe limits in both areas. VI. Cadmium (Cd) Data in table (8) show that the mean value of Cadmium (Cd) concentrations was 3.07 mg kg-1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while it was 0.05 mg kg-1 in those irrigated by ground water. The mean value of Cd concentrations was 3.22 mg kg-1 in the root dry matter of carrot, turnip and onion irrigated by sewage wastewater, while its concentrations was about 0.05 mg kg-1 in those irrigated by ground water. Cadmium (Cd) concentrations ranged between 0.07-0.08 mg kg-1 in the fruit dry matter of okra, tomato and
Egypt. J. Soil Sci. (2015)5:1-16 squash irrigated by sewage wastewater, while it ranged between 0.02-0.03 mg kg-1 in those irrigated by ground water. Cd concentrations in the above mentioned were above the permissible limits (EU, 2006 & WHO/FAO, 2007).
Irrig. water
Table (8) Cadmium concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water Cd Content (mg kg-1 Dry wt.) Value
Lettuce
Leaves Cabbage
Spinach
Carrot
Roots Turnip
Onion
Okra
Fruits Tomato
Squash
1.9
1.2
2.1
2.5
2.0
2.2
0.04
0.01
0.03
4.3
2.8
5.5
4.1
4.3
4.2
0.15
0.16
0.16
2.61±0.68
2.19±0.4
4.42±0.96
3.26±0.4
2.93±0.79
3.48±0.56
0.07±0.03
0.08±0.05
0.08±0.04
0.0
0.0
0.01
0.01
0.0
0.0
0.01
0.0
0.0
Min SW
Max Mean
#
Min GW
Max Mean# PL*
0.15
0.09
0.15
0.09
0.16
0.15
0.05
0.08
0.05
0.05±0.04
0.04±0.03
0.06±0.05
0.05±0.03
0.06±0.05
0.05±0.04
0.02±0.01
0.03±0.02
0.02±0.01
From 0.1 to 1.5
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
The Cd concentration in the edible portions could be arranged in descending order of leave > root > fruit. It can be concluded that irrigation with sewage wastewater increased Ni concentration in the leafy vegetables, edible roots and fruit by about 98.37, 98.35 and 69.57% respectively compared to irrigate by ground water. The high concentrations of Cd in roots may be linked to its low translocation within plant, compared to other elements (Voutsa et al., 1996). Similar results were reported by Ahsan et al. (2011) who investigated heavy metal contents in edible portions of vegetables and these found that Zn, Cu, Pb, Ni, Cd and Cr contents were higher than the safe limits. Also, Arora et al. (2008) reported the buildup of heavy metal in edible portion of vegetable. VII. Lead (Pb) Data illustrated in table (9) show that the mean value of Lead (Pb) concentrations was 5.58 mg kg-1 in leaves dry matter of lettuce, cabbage and spinach irrigated by sewage wastewater, while it was 0.20 mg kg-1 in those irrigated by ground water. The mean value of Pb concentrations was 5.13 mg kg-1 in the root dry matter of carrot, turnip and onion irrigated by sewage wastewater, while it was 0.02 mg kg-1 in those irrigated by ground water. Lead (Pb) concentrations ranged between 0.24-0.35 mg kg-1 in the fruit dry matter of okra, tomato and squash irrigated by sewage wastewater, while it ranged between 0.09-0.17 mg kg-1 in those irrigated by ground water. Using sewage wastewater in irrigation for more than 50 year resulted in concentrations of Pb exceeds the safe limits (0.3 mg kg–1) as described by WHO standards and can pose severe health effects. Sawidis et al. (2001) also found that leaves accumulate more 9
M. A. Youssef. and M. A. Eissa concentration of heavy metals than edible parts. Similar results were reported by (Ark et al., 2012). All heavy metals in the lettuce showed levels which were below the guide line FAO/WHO (2007). Heavy metals of public health concern like lead (Pb) and cadmium (Cd) were below detectable limit. However, measures have to be taken in other not to heavily pollute the irrigation water and soils with heavy metals to protect the safety of vegetable consumers and the general environment.
Irrig. water
Table (9) Lead concentration in edible parts of vegetable crops irrigated by sewage wastewater and ground water Pb Content (mg kg-1 Dry wt.) Value Min SW
Max Mean
#
Min GW
Max Mean# PL*
Lettuce
Leaves Cabbage
Spinach
Carrot
Roots Turnip
Onion
Okra
Fruits Tomato
Squash
3.5
2.2
4.2
3.1
4.1
3.6
0.08
0.1
0.03
6.1
6.4
9.2
8.1
7.2
7.2
0.5
0.6
0.8
4.79±0.75
4.90±1.21
7.04±1.67
5.19±1.52
5.25±1.18
4.95±0.92
0.24±0.16
0.35±0.15
0.35±0.22
0.0
0.1
0.1
0.06
0.12
0.01
0.01
0.1
0.01
0.35
0.3
0.5
0.35
0.34
0.45
0.3
0.35
0.4
0.16±0.12
0.17±0.08
0.28±0.13
0.19±0.07
0.21±0.06
0.20±0.11
0.09±0.08
0.16±0.08
0.17±0.11
From 0.03 to 5.0
* Permissible limits Guideline to (EU, 2006 & WHO/FAO, 2007). #Mean of (n=12) ± Standard Deviation.
The Pb concentration in the edible portion could be arranged in descending order of leave > root > fruit. It can be concluded that irrigation with sewage wastewater increased Ni concentration in the leafy vegetables and edible roots and by about 96.35 and 96.10% respectively compared to irrigate by ground water. The concentration of heavy metal by vegetables is not only affected by plant species and physicochemical characteristics of soil but temperature and rain fall also exert substantial effect. The results indicated that sewage wastewater caused a significant increase in heavy metals concentrations in the edible portion of the studied vegetables transfer of Cd and Pb from roots to shots are very low. Results in agreement with those of Rattan et al. (2005) and Lone et al.(2003). Also, Kadukova et al. (2004) found that the Pb stored in the root of plants was 93-98 % from the total Pb absorbed by plant. Wozny (1995) reported that roots can absorb Pb 3-50 times more than the leaves, this may be explain the high levels of Pb in roots of turnip, onion and carrot.
Conclusion
Egypt. J. Soil Sci. (2015)5:1-16 It might concluded that heavy metals accumulated in the edible vegetables that irrigated by sewage wastewater. In this study, obtained results showed that the leaves are the most edible portions that accumulated heavy metals followed by root then the least one is the edible fruits. It is worthy to mention that irrigated edible vegetable crops by SW should be avoided and guidelines should be developed for the reuse of wastewater. Therefore it is recommended to never use SW to irrigate vegetables unless it is obligated. SW might be used to irrigate their plants such as woody trees that can be used as a wind break, also energy producer plants. References Ahsan, I., Perveen, S., Shah, Z., Nazif, W. and Shah, H.U. (2011) Study on accumulation of heavy metals in vegetables receiving sewage water. Journal of the Chemical Society of Pakistan 33(2): 220-227. APHA (American Public Health Association). (2005) Standard Methods for Examination of water and wastewater. American Public Health Association, Washington, DC. Ark, O. A., Samuel, J. C. and Joseph A. A. (2012) Assessment of Heavy Metals in Lettuce Grown in Soils Irrigated with Different Water Sources in the Accra Metropolis, Res. J. Environ. Earth. Sci., 4(5): 576-582. Arora, M., Kiran, B., Rani, S., Rani, A. and Mittal, N. (2008) Heavy metal accumulation in vegetables irrigated with water from different sources. Journal of Food Chemistry 111: 811–815 Baker, D. E. and Amacher, M. C. (1982) "Nickel, Copper, Zinc and Cadmium", in A. L. Page et. al. (Eds), Methods of Soil Analysis, Part 2, Chemical and Microbiological Properties, 2 nd
ed., Agron. Monogr. Vol. 9, ASA and SSSA, Madison, WI, U.S.A.
Bigdeli, M. and Mohsen, S. (2008) Investigation of Metals Accumulation in Some Vegetables Irrigated with Waste Water in Shahre Rey-Iran and Toxicological Implications, Am-Euras. J. Agric. & Environ. Sci., 4 (1): 86-92. Buchholz, R. A. (1998) Principles of environmental management. The Greetings of Business. 2nd Prentice-Hall, London, U.K. Chary, N.S., Kamala, C.T. and Raj, D.S. (2008) Assessing risk of heavy metals from consuming food grown on sewage irrigated soils and food chain transfer. Ecotoxicol. Environ. Safety, 69(3): 513-524.
11
M. A. Youssef. and M. A. Eissa Chhabra, R. (1989) Sewage water, utilization through forestry. National Printers, Old Market, West Patel Nagar, New Delhi, India, p: 1-9. Demirezen, D. and Aksoy, A. (2006) Heavy metal levels in vegetables in Turkey are within safe limits for Cu, Zn, Ni and exceeded for Cd and Pb. J. Food Qual., 29: 252-265. Eissa, M. A. 2016. Effect of sugarcane vinasse and EDTA on cadmium phytoextraction by two saltbush plants. Environmental Science and Pollution Research 23(10), 10247-10254. DOI 10.1007/s11356-016-6261-9. Eissa, M. A., M. F. Ghoneim, G. A. Elgharably and M. AbdElRazek. 2014. Phytoextraction of nickel, lead and cadmium from metals contaminated soils using different field crops and EDT. World
Applied
Sciences
Journal
32
(6):
1045-1052.
DOI:
10.5829/idosi.wasj.2014.32.06.912 Eissa, M. A. 2017. Phytoextraction mechanism of Cd by Atriplex lentiformis using some mobilizing agents. Ecological Engineering (IF=2.91) 108, 220–226 Eissa, M. A. 2016. Phosphate and organic amendments for safe production of okra from metalcontaminated soils. Agronomy Journal, 108 (2): 540–547. doi:10.2134/agronj2015.0460 Eissa, M. A. and Suzie M. Reichman. 2016. Production of the forage halophyte Atriplex amnicola in metal-contaminated soils. Soil Use and Management 32, 350–356 Eissa, M. A. and M. A. Youssef. 2016. Comparison between organic and inorganic nutrition for tomato. Journal of Plant Nutrition 40:13, 1900-1907. Eissa, M. A., M. Nafady, H. Ragheb and K. Attia. 2014. Improving yield of drip- irrigated wheat under sandy calcareous soils. World Applied Sciences Journal
30 (7): 818-826. DOI:
10.5829/idosi.wasj.2014.30.07.11 Eissa, M. A., M. Nafady, H. Ragheb and K. Attia. 2014. Effect of Low and High Frequency of Phosphorus Fertigation on movement of different forms of phosphorus fertilizers in sandy calcareous soils. World Applied Sciences Journal 31 (12): 2045-2050. DOI: 10.5829/idosi.wasj.2014.31.12.637
Eissa, M. A. 2014. Performance of river saltbush (Atriplex amnicola) grown on contaminated soils as affected by organic fertilization. World Applied Sciences Journal, 30 (12): 1877-1881, DOI: 10.5829/idosi.wasj.2014.30.12.19
Egypt. J. Soil Sci. (2015)5:1-16 Eissa, M. A., M. Nafady, H. Ragheb and K. Attia. 2013. Effect of soil moisture and forms of phosphorus fertilizers on corn production under sandy calcareous soil. World Applied Sciences Journal 26 (4): 540-547, DOI: 10.5829/idosi.wasj.2013.26.04. 695.
EU. (European Union) (2006) Commission regulation (EC) No. 1881/2006 of 19 December setting maximum levels for certain contaminants in foodstuffs. Official Journal of European Union L364/5. EU. (European Union) (2002) Heavy Metals in Wastes European Commission on Environment (http: //ec.e uropa.eu/environment/waste/studies/pdf/heavy metals report.pdf). Fakayode, S.O. (2005) Impact of industrial effluents on water quality of the receiving Alaro River in Ibadan, Nigeria, Ajeam-Ragee, 10, 1-13. FAO (1985) Water Quality for Agriculture. Paper No. 29 (Rev. 1) UNESCO, Publication, Rome (Anonymous, Annual Progress Report (2000-03). NATP-MM Project on “Use of Urban and Industrial Effluents in Agriculture”. CSSRI, Karnal-Haryana, India, 2004. Farooq, M., Anwar, F. and Rashid, U. (2008) Appraisal of heavy metal contents in different vegetables grown in the vicinity of an industrial area. Pak. J. Bot., 40: 2099-2106. Faruqui, N.I., Scott, C.A. and Raschid-sally, L. (2004) Confronting the realities of waste water in irrigated agriculture: lessons learned and recommendations. IDRC Books Free online. http://www.idrc.ca. Fytianos, K., Katsianis, G., Trilantafyllou, P. and Zachariadis, G. (2001) Accumulation of heavy metals in vegetables grown in an industrial area in relation to soil. B. Environ. Contam. Toxicol., 67: 423-430. Ghimire, S. K. (1994) Evaluation of industrial effluents toxicity in seed germination and seedling growth of some vegetables, M.Sc. Dissertation, Central Department of Botany, Tribhuvan University, Kirtipur, Kathmandu, Nepal. Ghosh, A.K., Bhatt, M. A. and Agrawal, H. P. (2012) Effect of long-term application of treated sewage water on heavy metal accumulation in vegetables grown in northern India. Environ. Monit. Assess., 184(2): 1025-1036. Gupta, S. K., Scott, C. and Mitra, A. (2011) Advances in Land Resource Management for 21st Century, Soil Conservation Society of India, New Delhi, India,446-46. Huibers, F.P., Moscoso, O. A. and Lier, J.B.V. (2004) The use of waste water in cochabamba, Bolivia: a degrading environment. IDRC Books Free online. http://www.idrc.ca. 13
M. A. Youssef. and M. A. Eissa Kadukova, J., Papadontonakis, N., Naxakis, G. and Kalogerakis, N. (2004) Lead accumulation by the salt-tolerant plant Atriplex halimus. in: Moutzouris, C., Christodoulatos, C., Dermatas, D., Koutsospyros, A., Skanavis, C., Stamou, A., (Eds) eProceedings of the International Conference on Protection and Restoration of the Environment VII, June 28–July 1, Mykonos, Greece. Kanwar, J. S. and Sandha, M. S. (2000) Waste water pollution injury to vegetable crops, a review. Agric. Review., 21(2): 133-136. Khan, S. Q., Zheng, Y. M., Huang, Y.Z. and Zhu, Y.G. (2008) Health risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China. Environ. Pollution, 152(3): 686-692. Lone, M. I., Saleem, S., Mahmood, T., Saifullah, K. and Hussain, G. (2003) Heavy metal content of vegetables irrigated by sewage/tube well water., International J. Agric.& Biol., 4, 533-535. APHA (American Public Health Association), 2005. Standard Methods for Examination of water and wastewater. American Public Health Association, Washington, DC. Qadir, M., Wichelns, D. L., Raschid-Sally, P.G., McCornick, P., Drechsel, A. B. and Minhas, P.S. (2008) The challenges of wastewater irrigation in developing countries. Agric. Water Manag. http://www.sciencedirect.com. Rattan, R. K., Datta, S. P., Chhonkar, P. K., Suribabua, K. and Singh, A. K. (2005) Longterm impact of irrigation with sewage effluents on heavy metal content in soils, crops and groundwater-A case study., Agriculture, Ecosystems & Environ., 109, 310-32 Sawidis, T., Chettri, M. K., Papaionnou, A., Zachariasis, G. and Stratis, J. (2001) A study of metal distribution from lignite fuels using trees as biological monitors. Ecotoxicol. Environm. Safety, 48: 27-35. Sharma, R.K., Agrawal, M. and Marshall, F. M. (2006) Heavy metal contamination of soil and vegetables in suburban areas of Varanasi, India. Ecotoxicol. Environ. Safety, 66 (2): 258-266. Singh, A., Sharma, R. K., Agrawal, M. and Marshall, F.M. (2010) Health risk assessment of heavy metals via dietary intake of foodstuffs from the wastewater irrigated site of a dry tropical area of India. Food Chem. Toxicol., 48(2): 611- 619.
Egypt. J. Soil Sci. (2015)5:1-16 Ullah, H., Khan, I. and Ullah, I. (2011) Impact of sewage contaminated water on soil, vegetables and underground water of peri-urban Peshawar, Pakistan. Environ. Monit. Assess. Epub. ahead of print. http://www.ncbi.nlm.nih.gov/pubmed/22203410. Voutsa D., Grimanis A. and Samara C. (1996) Trace elements in vegetables grown in an industrial area in relation to soil and air particulate matter, J. Environmental Pollution, 94(34), p. 325-335. WHO/FAO (2007) Joint FAO/WHO Food Standard Programme Codex Alimentarius Commission 13th Session. Report of the Thirty Eight Session of the Codex Committee on Food Hygiene. Houston, United States of America, ALINORM 07/30/13. Wozny, A. (1995) Lead in plant cells. Sorus, Poland. Wang, J.Q., Ru, S.H., Su, D.C. (2004) Effects of nitrogenous fertilizers and chelators on absorption of cadmium by indian mustard and oilseed rape. J Agro Environ Sci 23, 625–629.
تراكم العناصر الثقيلة في الخضراوات التى تؤكل و المنزرعة فى أراضى ملوثة و ممدوح عبد الحفيظ عيسى1محمد أحمد يوسف
2
.قسم علوم األراضى والمياه– كلية الزراعة– جامعة األزهر– أسيوط– مصر .قسم علوم األراضى والمياه– كلية الزراعة– جامعة أسيوط– أسيوط – مصر
15
.1 .2
M. A. Youssef. and M. A. Eissa
في الوقت الحاضر ،ونتيجة الستداام مياه الصر
الصحي فى األنتاج الزراعى فى بعض المناطق األمر الذى نجم عنه آثار
بيئية دطيرة .فأن تقييم هذه اآلثار السلبية هو موضوع حيوي لمنع العناصر الثقيلة من الدخول في السلسلة الغذائية ،وقد تم اختيار ثالثة مواقع (قرية علوان ،منقباد و المدابغ) بمحافظة أسيوط خالل الموسمين 2012و2013م ،من أجل تقييم تركيزات العناصر الثقيلة في بعض محاصيل الخضر المنزرعة بمنطقة الدراسة .تنقسم محاصيل الخضر في الجزء الذي يؤكل منها لثالثة أجزاء )األوراق والجذور والثمار( تروى بواسطة مياه الصرف الصحي ) (SWأو مياه األبار ) (GWجمعت من مواقع مختلفة وتم تحليل محتواها من الحايا، المنجنيز ،الزنك ،النحاس ،الكااميوم ،النيكل و الرصاص. أظهرت النتائج المتحصل عليها أن األجزاء الورقية الصالحة لألكل من (الخس ،الكرنب والسبانخ) ذات محتوى عالي من العناصر الثقيلة مقارنة بجذور (الجزر واللفت والبصل) ،وقد سجلت أعلى تركيزات للعناصر الثقيلة بأوراق السبانخ المروية بمياه الصر
الصحى ،بينما كان أقل تركيز سجل بثمار البامية مقارنة بثمار محاصيل الخضر األخرى (الكوسا والطماطم) .جميع محاصيل
الخضر التي تروى بمياه جوفية كانت منخفضة في محتواها من العناصر الثقيلة مقارنة بمحاصيل الخضر المروية بمياه الصرف الصحي الجدير بالذكر هنا أن زراعة نباتات الخضر التي تؤكل خصوصا ً السبانخ والخس والبصل واللفت ،المروية بمياه الصرف الصحى ينبغى تجنبها .كذلك أظهرت الاراسة وجوب تسليط الضوء على المداطر المحتملة على صحة اإلنسان والحيوانات ،ذلك بسبب استيعاب تركيزات عالية من العناصر الثقيلة وخاصة الزنك ،الكادميوم والرصاص ،من خالل تناول العديد من محاصيل الخضر المنزرعة في أراضى ملوثة.
